Independent Wavefront Tailoring in Full Polarization Channels by Helicity-Decoupled Metasurface

Controlling the polarization and wavefront of light is essential for compact photonic systems in modern science and technology. This may be achieved by metasurfaces, a new platform that has radically changed the way people engineer wave-matter interactions. However, it still remains very challenging to generate versatile beams with independent wavefronts in each polarization channel by a single ultrathin metasurface. By modulating both the geometric and propagation phases of the metasurface, here a method is proposed that can generate an assembly of circularly and linearly polarized beams with simultaneously the capability of independent encoding desired wavefront to each individual polarization channel, which is believed to greatly enhance the information capacities of the metadevices. Two proof-of-concept designs are experimentally demonstrated in microwave region. Upon the excitation of an arbitrary linear polarization, the first device can generate distinct vortex beams with the desired two linear and two circular orthogonal polarizations, whereas the second one can generate multifoci containing components of full polarizations. This approach to generate versatile polarizations with tailored wavefront may pave a way to achieve advanced, flat, and multifunctional metadevice for integrated systems.

Automated summary

Controlling the polarization and wavefront of light is crucial for compact photonic systems. By using metasurfaces, a new platform that changes the way wave-matter interactions are engineered, a method is proposed to generate versatile beams with independent wavefronts in each polarization channel. Two proof-of-concept designs have been experimentally demonstrated in the microwave region.